Electrical enclosures, such as, for example, load centers or panelboards, typically house multiple circuit breakers and/or related electrical accessories. Panelboards typically include one main vertical feeder bar or busbar per phase of electricity to be distributed to a protected load. Panelboards include an outer housing that limits the space available for installing circuit breakers. Additionally, regulations restrict a circuit breaker's handle height from being above a prescribed height within a panelboard. Such a regulation further limits the space available for installing circuit breakers in a panelboard having a vertical busbar configuration, as the busbars can only be vertically extended to the prescribed height. Thus, panelboards typically include the same-sized circuit breakers having the same ampacity to maximize the number of circuit breakers that a panelboard can accommodate, as the circuit breakers are typically installed side-by-side along the vertical busbar(s).
Some prior art panelboards include two or more panelboards coupled together side-by-side to provide a product having an increased capacity for a variety of different sized circuit breakers. One such product is, for example, an Integrated Power Center, provided by Schneider Electric USA Inc., which includes two or more separate housings containing differently rated circuit breakers. One of the housings includes a power panel for receiving an electrical input and a second one of the housings includes, for example, a lighting panel. The power panel is electrically coupled to the lighting panel through wires transitioning between the two housings. The two housings can be bulky and require a significant amount of space and installation time on, for example, a construction site. Moreover, much of the space can be wasted inside the housing, particularly in installations in which only a few circuit breakers are needed to protect multiple branch circuits.
Thus, a need exists for an improved apparatus. The present invention is directed to satisfying one or more of these needs and solving other problems.